Many of you are familiar with performance optimization, either to achieve better system performance or to meet increasing business requirements.

All need to use our performance tuning. So performance optimization comes up particularly often in interviews

I think I know a lot about performance optimization, and because I am currently in a job interview, I have reviewed a lot of indexes separately.

I didn’t realize that MY knowledge of performance optimization was at an elementary school level until I was abused by ali’s interviewer.

Here are my summary of performance optimization interview questions and knowledge points from an interview with Ali.

Tomcat performance tuning

  1. How do I tune Tomcat
  2. How to increase the number of COMCAT connections
  3. How to increase tomcat memory
  4. How do I disable files in a column directory in Tomcat
  5. Tomcat can be deployed in several ways
  6. Tomcat optimization experience

JVM Performance Optimization Topics:

  1. Java class loading process
  2. Java memory allocation
  3. Describe how the JVM loads class files
  4. What is GC? Why GC?
  5. Describe the Java garbage collection mechanism
  6. How do you tell if an object is alive? (or GC object determination method)
  7. Advantages and principles of garbage collection. Two recycling mechanisms are considered.
  8. What is the rationale behind the garbage collector? Can the garbage collector reclaim memory right away?
  9. Is there any way to proactively notify the virtual machine for garbage collection?
  10. Is there a memory leak in Java? Please describe it briefly.
  11. Deep copy and shallow copy
  12. What does syatem, gc() and Runtime, GC () do?
  13. When is finalize method called? What is the purpose of finalizatinon?
  14. If a reference to an object is set to NULL, does the garbage collector immediately free the memory occupied by the object?
  15. What is Distributed Garbage Collection (DGC)? How does it work?
  16. What is the difference between the Serial collector and the throughput collector?
  17. When can objects be garbage collected in Java?
  18. Briefly describe the Java memory allocation and reclamation policy and minor GC and majorGC.
  19. Does garbage collection occur in the JVM’s permanent generation?
  20. What are the methods of garbage collection in Java?
  21. What is a class loader, and what are class loaders?

Mysql performance optimization (mind map) :

Mind mapping

Performance optimization has always been one of the focuses of company interview, hope that the students can learn knowledge from this article, combing out their own learning route, at the same time as a result of the limitation of the length of the article, this paper questions the answer is no list, have need answers and hd study thinking route map friend can concern WeChat public number: Java programmers